PCV On A 2012 5.3L

[diyer2]

There is no actual PCV valve on this motor.

It's just a tube.

Seems odd to me.

Why?

 

[Grumpy Bear]

4 minutes ago, diyer2 said:

There is no actual PCV valve on this motor.

It's just a tube.

Seems odd to me.

Why?

 

True of the 4.3 LV3 as well. There is some serious baffling/demisters in the valve covers. True vapor is still routed to the lower pressure inlet box but the mist is eliminated when in designed operation. My tube is always dry. In part I believe the lower volume oiling system also eliminated the bulk of the mist creation. Add factory windage tray...….factory rings that seal better.....

 

Once I had a glitch in the ECM that kept the oil dump solenoid closed while I was on the interstate, (45 psi measured) a toll road where stopping was discouraged so I had to run about 20 miles to the next exit. There was oil in the tube....only time. Cycling the key cleared the fault and it's never happened again but I learned from it. 

 

 

[diyer2]

Ok 

Makes sense.

I learned this when I put my catch can on a while back.

My PCV tube had some oil in it.

 

[Jsdirt]

They were using a fixed orifice system for a while there, instead of an actual valve. It must have this in addition to the baffling, otherwise you'd be pulling quarts of oil into the intake

[diyer2]

Fixed orifice?

It's a tube.

Might as well be a piece of tubing.

 

Here's the story.

My thought was this PCV valve has 60+ k miles on it so why not put on a new one when I install my new catch can.

Before putting my catch  can on I bought a PCV tube figuring it had a real PCV valve in it.

Got the part new off eBay for $7 including shipping, so why not.

Inspecting the part when it arrived it was a tube, no PCV valve like I thought.

 

Thus this post.

Not a big deal, truck runs great.

 

 

[Jsdirt]

The tube should LEAD to a fixed orifice, either in the block or in the valve cover.

[diyer2]

13 minutes ago, Jsdirt said:

The tube should LEAD to a fixed orifice, either in the block or in the valve cover.

Ok I didn't look for that.

[Doug_Scott]

The 5/16" hole in the fitting on the intake manifold could be considered a "fixed oriface" tube. I would imagine the part that was purchased from ebay was likely just the pre-formed tube that runs from manifold to rocker covers. 

 

The catch can on my truck catches about 3 or 4 ounces between oil changes done strickly by oil life monitor. 

[Grumpy Bear]

58 minutes ago, Doug_Scott said:

The 5/16" hole in the fitting on the intake manifold could be considered a "fixed oriface" tube. I would imagine the part that was purchased from ebay was likely just the pre-formed tube that runs from manifold to rocker covers. 

 

The catch can on my truck catches about 3 or 4 ounces between oil changes done strickly by oil life monitor. 

There you have it.